package com.cjm.algorithm.dp;

public class Ti63 {
    public static void main(String[] args) {
        Ti63 ti63 = new Ti63();
        int[][] xx = {{0,0,0}, {0,1,0},{0,0,0}};
        int i = ti63.uniquePathsWithObstacles(xx);
        System.err.println("OK");
    }
    public int uniquePathsWithObstacles(int[][] obstacleGrid) {
        int m = obstacleGrid.length;
        int n = obstacleGrid[0].length;

        int[][] dp = new int[m][n];
        dp[0][0] = 0;
        // 第一行
        boolean flag = false;
        for (int i = 1; i < n; i++) {
            if (obstacleGrid[0][i] == 1) {
                dp[0][i] = 0;
                flag = true;
            } else {
                if (flag) {
                    dp[0][i] = 0;
                } else {
                    dp[0][i] = 1;
                }
            }
        }

        // 第一列
        flag = false;
        for (int i = 1; i < m; i++) {
            if (obstacleGrid[i][0] == 1) {
                dp[i][0] = 0;
                flag = true;
            } else {
                if (flag) {
                    dp[i][0] = 0;
                } else {
                    dp[i][0] = 1;
                }
            }
        }

        for (int i = 1; i < m; i++) {
            for (int j = 1; j < n; j++) {
                if (obstacleGrid[i][j] == 1) {
                    dp[i][j] = 0;
                } else {
                    dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
                }
            }
        }
        return dp[m - 1][n - 1];
    }
}
